This invention uses solar energy to power a direct current (DC) load system as well as using rechargeable batteries to store the power that can be generated by solar energy to support a DC load. More particularly this invention not only protects the rechargeable battery from over discharge and also targets various needs of the user to create several combination systems including: a water pump combined with an illuminating system, a water pumping system, and an illumination system that includes at least one LED. These combination systems can synchronize the day and night cycles to turn on and off automatically.
The prior art showed some control circuits or apparatus that used solar energy to power a water pump system, or lighting system or battery protection control system. The US Patent to U.S. Pat. No. 5,569,998, filed Oct. 29, 1996, by Thomas Cowan, indicated that the apparatus controlled a water pumping system with complex control circuits and a high number of components such as voltage reference generator, voltage interpreter, charge current simulator, voltage comparator, and complex charge switch driver ext. This apparatus only can be used for home and the prior art only controls a water pumping system without an illuminating system.
From the US Patent Application Publication number 2008/0185988 A1, filed Feb. 7, 2007, by Chen-Yueh Fan, the control circuit shows that solar garden light device needs an external DC power source which creates additional installation work for the users to support this garden lights. One of embodiments of the present invention has an illumination system which includes at least one LED without the external DC power source. The present invention also shows different circuits and components over the prior art. The present invention can combine the illumination system with the water pumping system.
The current invention has dramatic advantages which are more powerful functionalities and wider range of usage with reliable control circuits that can be put in one apparatus with varied functionality that target different working hours based on daily and seasonal cycles and different need of users.